Newfound marker for aggressive breast cancer may also be a treatment target

The findings of a recent study strongly implicate the ribonucleic acid (RNA) molecule miR-181a as a predictive biomarker for breast cancer metastasis and patient survival, which in turn makes the molecule a potential therapeutic target in metastatic breast cancer.

As explained in a statement issued by Case Western Reserve University in Cleveland, Ohio, miR-181a had never before been tied to breast cancer metastasis. However, William P. Schiemann, PhD, of the Case Comprehensive Cancer Center, and colleagues found elevated levels of the molecule in late-stage breast cancer tissues.

The investigators described in The Journal of Clinical Investigation (2013;123[1]:150-163) their discovery that miR-181a expression was essential in driving metastasis and enhancing the lethality of late-stage mammary tumors in mice. In addition, miR-181a expression was dramatically and selectively upregulated in metastatic breast tumors, particularly triple-negative breast cancers, and was highly predictive for decreased overall survival in humans with breast cancer.

An inhibitor of miR-181a tested in the mice prevented metastasis and extended survival.

“Overall, these findings reinforce our belief that the discovery of miR-181a will become a strong predictive biomarker for breast cancer metastasis, and that the high expression of miR-181a in tumor tissues will pave the way for the development of targeted therapies, better prognosis, and increased patient survival,” commented Schiemann in the Case Western statement.